The invention relates to the efficient and cost-effective recovery of component materials from carpet waste.
Current processes for recovering carpet waste components often require complicated and expensive integration of numerous unit operations, and yet achieve modest results. In particular, efforts to recover materials from carpet waste most often subject a feedstock of dirty, post-consumer, whole carpet to one of several separation techniques. Unfortunately, some materials and impurities present in used carpet (e.g., some adhesives and dirt) necessitate numerous washing and screening steps, which impede the effectiveness of most separation processes. Reduced efficiency frequently renders recovery of the desired components costly, and thus impractical.
Various mechanical separation processes have been attempted to separate and recover materials from carpet waste. One common method is hot-wire skimming or shearing nylon pile from the carpet surface. This approach, however, recovers only the face fiber that extends above the carpet backing. Consequently, it is not an effective method for recovering the significant portion of face fiber found below the carpet backing.
Other processes attempt to separate carpet components by first reducing the size of the carpet waste and thereafter separating the size-reduced component materials, such as via elutriators, centrifuges, hydrocyclones, and settlers. Each kind of apparatus carries its own advantages and disadvantages, but as of yet none has been employed in a way that provides cost-effective recycling of carpet waste.
Carpet manufacturers are continually challenged by the generation of post-industrial carpet waste. Each year, large quantities of such carpet waste are simply landfilled. Disposing of carpet waste in this way is not only expensive, but also runs counter to increasing corporate emphasis on environmental stewardship. In short, merely discarding carpet waste precludes recycling the useful materials present in carpet waste.
Consequently, the need exists for an efficient and cost-effective method to separate and recover the components of carpet waste such that the recovered materials are sufficiently pure to facilitate immediate recycling.
Therefore, it is an object of the present invention to provide an efficient and cost-effective method for recovering component materials from carpet waste.
It is further an object of the present invention to provide an efficient and cost-effective method for recovering component materials from post-industrial, pre-consumer waste.
It is further an object of the present invention to provide a cost-effective method for recovering the component materials of carpet waste that includes only polymer face fiber and olefin fabric backing.
It is further an object of the present invention to selectively separate the components of pre-consumer carpet waste in such a manner as to result in an output stream of polymer face fiber that is pure enough to facilitate direct processing of the recovered face fiber.
It is yet another object of the present invention to separate the components of pre-consumer carpet waste in such a manner as to result in an output stream of olefin backing fiber that is pure enough to facilitate direct processing of the recovered olefin backing fiber.
It is further an object of the present invention to lessen the environmental impact of disposing of carpet waste in landfills by providing an economically-viable recycling method.
The foregoing, as well as other objectives and advantages of the invention and the manner in which the same are accomplished, is further specified within the following detailed description and its accompanying drawings.